1. Field of the Invention
This invention relates generally to electricity, measuring and testing and more particularly to magnetic information storage element testing.
2. Description of the Prior Art
A new generation of magnetic recording disk memory for computers uses plated or sputtered magnetic films as thin as 0.08 microns thick. Contrasting to the relatively softer disk surface, the associated recording head slider uses hard ceramic material. Spacing as close as 0.2 to 0.4 microns between the slider and disk is maintained by an aerodynamic bearing generated in the spacing at a disk surface speed of about 50 meters per second. The proper operation of the magnetic recording depends critically on the integrity of the interface which consists of the thin magnetic film, the slider surface and the dynamic air bearing. Wear of the film can occur due to contact between the slider and disk. The wear may be due to start/stop contact, in some types of recorders, or may be due to contacts caused by unwanted influences such as vibrations. The wear resulting from the impact of the slider on the disk surface must be controlled to the amount equal to or preferably less than one-half of the roughness of the disk surface.
At present, slider/disk interface wear is evaluated by a method in which the disk drive is used to accumulate the contact start-stop and/or seek motion cycles while the magnetic recording performance is monitored. This is a sound and complete test; however, it is costly, time consuming and provides limited understanding about the wear mechanisms which are required to meet the challenge of controlling the ever increasing sensitivity to wear of the head/disk interface.
The foregoing illustrates limitations of the known prior art. Thus, it is apparent that it would be advantageous to provide an alternative directed to overcoming one or more of the limitations as set forth above. Accordingly, a suitable alternative is to provide apparatus for measuring and characterizing slider/disk wear.